Sirolimus conversion after liver transplantation: improvement in measured glomerular filtration rate after 2 years

Nonalcoholic Steatohepatitis After Liver Transplantation

Currently, nonalcoholic steatohepatitis (NASH) is the second leading indication for liver transplantation (LT), behind alcohol-related liver disease. After transplant, both recurrent and de novo nonalcoholic fatty liver disease are common; however, recurrence rates of NASH and advanced fibrosis are low. Identification of high-risk groups and optimizing treatment of metabolic comorbidities both before and after LT is paramount to maintaining a healthy allograft, especially with the additional consequences of longterm immunosuppression. In addition, NASH LT recipients are at an increased risk of cardiovascular events and malignancy, and their condition warrants a tailored approach to management. The optimal approach to NASH LT recipients including metabolic comorbidities management, tailored immunosuppression, the role of bariatric surgery, and nutritional and pharmacotherapy of NASH are discussed in this review. Overall, aggressive management of metabolic syndrome after LT via medical and surgical modalities and a minimalist approach to immunosuppression is advised.

The benefit of sirolimus maintenance immunosuppression and rabbit antithymocyte globulin induction in liver transplant recipients that develop acute kidney injury in the early postoperative period

Published data are limited describing renal outcomes in orthotopic liver transplant (OLT) recipients prescribed sirolimus (SRL) maintenance immunosuppression (MIS) and rabbit antithymocyte globulin (rATG) induction. We investigated whether SRL MIS and rATG induction facilitated recovery of acute kidney injury in the early postoperative period. This retrospective descriptive study screened 308 consecutive OLTs performed between 2006 and 2009. All patients received rATG induction with steroid avoidance. MIS consisted of SRL or TAC with mycophenolate mofetil. A total of 197 patients were included: 168 (85%) received TAC and 29 (15%) received SRL for a median of 365 days. Demographics were similar between groups except for a higher incidence of pretransplant renal dysfunction in the SRL recipients (SRL 59% versus TAC 21%; P < 0.05). The eGFR was significantly (P < 0.05) higher for all time points in the TAC group with the exception of month 2. However, improvement in eGFR was significantly (P < 0.05) greater in the SRL group postoperatively. Our study suggests that rATG induction and SRL maintenance immunosuppression facilitate renal recovery for liver transplant recipients that develop acute kidney injury in the early postoperative period.

Conversion from calcineurin inhibitors to mTOR inhibitors stabilizes diabetic and hypertensive nephropathy after liver transplant

AIM: To investigate if conversion to the mammalian target of rapamycin inhibitors (mTORi) improves renal function in diabetic and/or hypertensive liver transplant patients immunosuppressed with tacrolimus or cyclosporine.

METHODS: The study included 86 liver graft recipients immunosuppressed with mTORi treatment after orthotopic liver transplantation (OLT), including all liver recipients with worsening renal function before conversion to mTORi (n = 55 patients) and recipients with normal renal function who converted to mTORi for other reasons (n = 31 patients). We identified patients with diabetes mellitus (n = 28), arterial hypertension (n = 27), proteinuria (n = 27) and all three factors (n = 8) (some patients have hypertension and diabetes and no proteinuria). The primary endpoint was evolution in renal function defined as the development in plasma creatinine as a function of diabetes mellitus (DM), hypertension (HT) or proteinuria. We required elevated serum creatinine for at least two weeks to define renal dysfunction.

RESULTS: Only patients that converted because of renal failure with plasma creatinine levels > 1.5 mg/dL showed an improvement of renal function (2.14 to 1.77 mg/dL) (P = 0.02). Patients with DM showed no improvement of serum creatinine levels (1.31 mg/dL to 1.37 mg/dL) compared with non DM patients (1.31 mg/dL to 1.15 mg/dL) (P = 0.01), HT patients (1.48 mg/dL to 1.5 mg/dL) with non HT patients (1.21mg/dL to 1.08 mg/dL) and patients with proteinuria (1.44 mg/dL to 1.41 mg/dL) and no proteinuria (1.31 mg/dL to 1.11 mg/dL).

CONCLUSION: In OLT recipients with diabetes or hypertensive nephropathy, conversion to mTORi does not improve renal function but stabilizes plasma levels of creatinine. Proteinuria is not a contraindication to conversion to mTORi; it also stabilizes renal function. Conversion to mTORi should only be avoided in patients with diabetes, hypertension and proteinuria.

Improving long-term outcomes after liver transplantation

Long-term survival following liver transplantation is profoundly affected by conditions unrelated to graft function. Many causes of mortality are contributed to by the metabolic syndrome. The approach to metabolic syndrome in liver transplant recipients requires consideration of transplant-specific factors, particularly immunosuppression. Enhancing long-term outcomes for liver transplant recipients necessitates minimizing the amount of immunosuppression required to prevent rejection. Studies to determine the optimal approach to minimize the impact of metabolic syndrome and complications of immunosuppression in transplant recipients are needed.

The Role of mTOR Inhibitors in Liver Transplantation: Reviewing the Evidence

Despite the success of liver transplantation, long-term complications remain, including de novo malignancies, metabolic syndrome, and the recurrence of hepatitis C virus (HCV) and hepatocellular carcinoma (HCC). The current mainstay of treatment, calcineurin inhibitors (CNIs), can also worsen posttransplant renal dysfunction, neurotoxicity, and diabetes. Clearly there is a need for better immunosuppressive agents that maintain similar rates of efficacy and renal function whilst minimizing adverse effects. The mammalian target of rapamycin (mTOR) inhibitors with a mechanism of action that is different from other immunosuppressive agents has the potential to address some of these issues. In this review we surveyed the literature for reports of the use of mTOR inhibitors in adult liver transplantation with respect to renal function, efficacy, safety, neurological symptoms, de novo tumors, and the recurrence of HCC and HCV. The results of our review indicate that mTOR inhibitors are associated with efficacy comparable to CNIs while having benefits on renal function in liver transplantation. We also consider newer dosing schedules that may limit side effects. Finally, we discuss evidence that mTOR inhibitors may have benefits in the oncology setting and in relation to HCV-related allograft fibrosis, metabolic syndrome, and neurotoxicity.

Anti-CD25 monoclonal antibody replacement therapy for chronic kidney disease in liver transplant recipients

BACKGROUND

Chronic kidney disease (CKD) is a frequent complication after liver transplantation (LT) and is associated with increased mortality. Strategies to reduce calcineurin inhibitor (CNI) dose or conversion to either mycophenolate mofetil and/or rapamycin resulted in variable results and side-effect profiles.

METHODS

We evaluated the effectiveness of CNI conversion to long-term anti-CD25 monoclonal antibody (mAb)-based immunosuppression in 15 adult LT patients with CKD at 7.6±4 years posttransplant (intervention group). Three patients had been previously switched to rapamycin, and 12 patients were on CNI. The control group included 15 LT patients on CNI with stable renal function over a similar posttransplant follow-up period.

RESULTS

Anti-CD25 mAb were given over a period of 26±15 months (range, 2-51 months) and were well tolerated. The slope of calculated creatinine clearance was -0.66 mL/min/month over 6 months before conversion and -0.05 mL/min/month after conversion to anti-CD25 mAb (P=0.16 and P=0.86 vs. controls). Three acute rejection episodes occurred in the intervention group. Acute rejection was reversible in two patients. However, one patient died of chronic rejection 1 year after having been switched to tacrolimus. Anti-CD25 mAb were replaced with either CNI or rapamycin in six patients (acute rejection [n=2], progression to end-stage renal disease [n=2], poor venous status [n=1], increased liver enzymes [n=1]).

CONCLUSION

The use of long-term anti-CD25 mAb therapy as a replacement to CNI and rapamycin-based immunosuppression may be feasible. It is crucial that rejection surveillance is intensified. A randomized controlled trial is required to confirm the benefits of this strategy.

Sirolimus conversion in liver transplant recipients with calcineurin inhibitor-induced complications: efficacy and safety

OBJECTIVES

To evaluate the efficacy and safety of conversion from calcineurin inhibitors to sirolimus among liver transplant recipients with calcineurin inhibitor-induced complications.

MATERIALS AND METHODS

After receiving liver transplants, 25 patients with calcineurin inhibitor-induced complications (22 renal dysfunction and 3 new-onset diabetes mellitus) were converted from sirolimus to tacrolimus. The serum creatinine, sirolimus trough level, liver function, acute rejection episodes, and drug-related adverse effects were monitored.

RESULTS

The patients were followed for 12 to 50 months (median, 25 months). The renal function of the 22 patients with renal dysfunction improved after sirolimus conversion. The serum creatinine levels were significantly lower at 3 months after conversion versus before conversion (113.2 ± 21.8 μmol/L vs 163.2 ± 45.3 μmol/L; P < .05). At the end of the follow-up, the average serum creatinine level was 101.9 ± 23.4 μmol/L among the 20 living recipients. Diabetes also was under control in 3 diabetic recipients after the conversion. Four patients experienced episodes of acute rejection, and intravenous steroid bolus therapy was administered in 2 of them. No graft was lost because of acute rejection. The adverse effects of sirolimus included hyperlipidemia (7/25), anemia (8/25), and mouth ulcers (9/25). All these adverse effects were relieved after a short-term symptomatic therapy, and no patient was withdrawn from the conversion trial.

CONCLUSIONS

Sirolimus monotherapy is effective and safe in liver transplant recipients. Conversion to sirolimus was associated with a sustained improvement in renal function and diabetes mellitus without an increased incidence of acute rejection episodes.

Sirolimus conversion regimen versus continued calcineurin inhibitors in liver allograft recipients: a randomized trial

A large prospective, open-label, randomized trial evaluated conversion from calcineurin inhibitor (CNI)- to sirolimus (SRL)-based immunosuppression for preservation of renal function in liver transplantation patients. Eligible patients received liver allografts 6-144 months previously and maintenance immunosuppression with CNI (cyclosporine or tacrolimus) since early posttransplantation. In total, 607 patients were randomized (2:1) to abrupt conversion (<24 h) from CNI to SRL (n = 393) or CNI continuation for up to 6 years (n = 214). Between-group changes in baseline-adjusted mean Cockcroft-Gault GFR at month 12 (primary efficacy end point) were not significant. The primary safety end point, noninferiority of cumulative rate of graft loss or death at 12 months, was not met (6.6% vs. 5.6% in the SRL and CNI groups, respectively). Rates of death at 12 months were not significantly different, and no true graft losses (e.g. liver transplantation) were observed during the 12-month period. At 52 weeks, SRL conversion was associated with higher rates of biopsy-confirmed acute rejection (p = 0.02) and discontinuations (p < 0.001), primarily for adverse events. Adverse events were consistent with known safety profiles. In conclusion, liver transplantation patients showed no demonstrable benefit 1 year after conversion from CNI- to SRL-based immunosuppression.

Calcineurin-inhibitor minimization in liver transplant patients with calcineurin-inhibitor-related renal dysfunction: a meta-analysis

Background

Introduction of calcineurin-inhibitor (CNI) has made transplantation a miracle in the past century. However, the side effects of long-term use of CNI turn out to be one of the major challenges in the current century. Among these, renal dysfunction attracts more and more attention. Herein, we undertook a meta-analysis to evaluate the efficacy and safety of calcineurin-inhibitor (CNI) minimization protocols in liver transplant recipients with CNI-related renal dysfunction.

Methods

We included randomized trials with no year and language restriction. All data were analyzed using random effect model by Review Manager 5.0. The primary endpoints were glomerular filtration rate (GFR), serum creatinine level (sCr) and creatinine clearance rate (CrCl), and the secondary endpoints were acute rejection episodes, incidence of infection and patient survival at the end of follow-up.

Results

GFR was significantly improved in CNI minimization group than in routine CNI regimen group (Z = 5.45, P<0.00001; I² = 0%). Likely, sCr level was significantly lower in the CNI minimization group (Z = 2.84, P = 0.005; I² = 39%). However, CrCl was not significantly higher in the CNI minimization group (Z = 1.59, P = 0.11; I² = 0%). Both acute rejection episodes and patient survival were comparable between two groups (rejection: Z = 0.01, P = 0.99; I² = 0%; survival: Z = 0.28, P = 0.78; I² = 0%, respectively). However, current CNI minimization protocols may be related to a higher incidence of infections (Z = 3.06, P = 0.002; I² = 0%).

Conclusion

CNI minimization can preserve or even improve renal function in liver transplant patients with renal impairment, while sharing similar short term acute rejection rate and patient survival with routine CNI regimen.

Basiliximab induction and delayed calcineurin inhibitor initiation in liver transplant recipients with renal insufficiency

BACKGROUND

Renal insufficiency (RI) is common after liver transplantation (LT) and may worsen due to calcineurin inhibitor (CNI) use. We compared LT outcomes using basiliximab induction and delayed CNI initiation to controls with a standard CNI regimen in patients with peri-LT RI.

METHODS

All adults transplanted January 2004 to December 2007 with peri-LT RI (hemodialysis or creatinine ≥1.5 within 1 week of LT) were included in a retrospective nonrandomized cohort. Outcomes including 30-day and 1-year patient and graft survival and renal function were compared between basiliximab and control groups.

RESULTS

Two hundred twenty-nine patients (102 basiliximab, 127 controls) were analyzed, mean age 54 years, 72% men, 54% with hepatitis C virus. Mean model for end-stage liver disease (28.2 vs. 20.0; P<0.001) and creatinine (1.9 vs. 1.6; P=0.001) were higher and more patients were on hemodialysis at LT (29% vs. 6%; P<0.001) in the basiliximab group. 30-day patient (99% vs. 97%; P=0.26) and graft survival (98% vs. 95%; P=0.17), 1-year patient (87% vs. 87%; P=0.89) and graft survival (86% vs. 82%; P=0.37), mean creatinine at 1-year (1.5 vs. 1.5 mg/dL; P=0.82), and treated acute rejection (6% vs. 6%; P=0.90) were similar between basiliximab and control groups, respectively. In multivariable logistic regression, basiliximab was not significantly associated with 30-day (odds ratio, 0.10; P=0.11) or 1-year (odds ratio, 0.97; P=0.94) survival, controlling for age, previous LT, model for end-stage liver disease, and hepatitis C virus.

CONCLUSIONS

Basiliximab induction resulted in 30-day and 1-year patient, graft and renal outcomes comparable with a control group receiving standard CNI-based immunosuppression. Antibody induction with delayed CNI should be further studied prospectively.

Suitable calcineurin inhibitor concentrations for liver transplant recipients in the Chinese population

AIM

The aim was to deduce suitable calcineurin inhibitor concentrations for the Chinese liver transplantation population.

METHODS

We retrospectively studied 97 liver transplant recipients who displayed stable liver and renal function. No grafts were obtained from prisoners, procurements were performed with donor consent conforming to international ethics regulations. At 3, 6, and 12 months, we increased the concentrations and doses of calcineurin inhibitors as well as the values of alanine transaminase and serum creatinine.

RESULTS

Twenty-eight recipients received cyclosporine and 69 tacrolimus. The mean cyclosporine daily dosages were 203 ± 62 mg at 3, 188 ± 55 mg at 6, and 173 ± 52 mg at 12 months, the tacrolimus daily dosages were 3.08 ± 0.98, 2.82 ± 0.98, and 2.58 ± 0.93 mg, respectively. The corresponding mean cyclosporine peak concentrations (C(2)) were 806 ± 322 ng/mL, 681 ± 206 ng/mL, and 644 ± 190 ng/mL and the mean tacrolimus trought concentrations (C(0)) 6.61 ± 3.02 ng/mL, 5.85 ± 2.44 ng/mL, and 5.22 ± 2.33 ng/mL, respectively. In both groups, transaminases and serum creatinine were stable over time.

CONCLUSIONS

An individualized immunosuppressive regimen for the local population is necessary. We delayed calcineurin inhibitors with subsequent low-dose mycophenolate mofetil plus minimized calcineurin inhibitors, which seemed to be nephroprotective and safe for Chinese liver transplantation patients.

Switching to sirolimus-based immune suppression after liver transplantation is safe and effective: a single-center experience

BACKGROUND

Sirolimus is unlicensed for use in liver transplantation because of concerns over safety, particularly in regard to hepatic artery thrombosis and excess mortality. However, sirolimus offers potential advantages over calcineurin inhibitor-based immunosuppression, relating to its renal sparing and antiproliferative properties.

METHODS

A review was undertaken of 148 liver transplant patients converted to sirolimus over 10 years at a single center.

RESULTS

The main indications for sirolimus were renal impairment and hepatitis C virus fibrosis. One hundred eleven (75%) patients remained on sirolimus after median follow-up of 1006 days. Mean (+/-standard deviation) glomerular filtration rate improved significantly from 59+/-29 mL/min preconversion to 72+/-39 mL/min at censor point (P<0.05). Improvement in glomerular filtration rate was most marked in patients converted for renal impairment. Liver function tests remained stable or improved, particularly in patients transplanted for hepatitis C virus. Side effects attributed to sirolimus occurred in 101 (68%) patients requiring withdrawal in 20 patients (14%). Moderate increases in serum lipids were observed and controlled effectively with statins. The incidence of proteinuria increased postconversion but had no deleterious impact on renal function. No episodes of hepatic artery thrombosis were observed.

CONCLUSIONS

Sirolimus was safe and may improve outcome in selected patients after liver transplantation.

Causes of sirolimus discontinuation in 97 liver transplant recipients

INTRODUCTION

Sirolimus is a potent immunosuppressant with a mechanism of action different from calcineurin inhibitors (CNIs). It has increasing importance for liver transplant (OLT) patients, in particular if when there is decreased renal function. We evaluated the efficacy and the causes for discontinuation of sirolimus-based immunosuppression among OLT recipients.

OBJECTIVE

We retrospectively analyzed 97 liver transplanted patients who were prescribed sirolimus as the principal immunosuppressant. Of these, 61 patients discontinued treatment. Herein we have reported the causes, the timing, and the effects of sirolimus discontinuation.

RESULTS

The overall patient survival at 3 years follow-up was 89%. Hepatotoxicity and blood disorders were the most frequent, severe reported side effects. Acute cellular rejection episodes appeared in seven patients and was relieved in 1 to 2 weeks after the sirolimus administration. In 10 patients, the cholestasis associated with chronic rejection was sharply reduced after the introduction of sirolimus. No increase in vascular thrombosis and/or poor wound healing were reported.

CONCLUSION

Sirolimus given alone or in combination with CNIs appears to be an effective primary immunosuppressant regimen for OLT patients. However, in the late postoperative period (>3 months) the drug is associated with a relatively high rate of side effects.

Mycophenolate monitoring in liver, thoracic, pancreas, and small bowel transplantation: a consensus report

Assessing the value of mycophenolic acid (MPA) monitoring outside renal transplantation is hindered by the absence of any trial comparing fixed-dose and concentration-controlled therapy. However, in liver and thoracic transplantation particularly, clinical trials, observational studies with comparison groups, and case series have described MPA efficacy, exposure/efficacy relationships, pharmacokinetic variability, and clinical outcomes relating to plasma MPA concentrations. On the basis of this evidence, this report identifies MPA as an immunosuppressant for which the combination of variable disposition, efficacy, and adverse effects contributes to interindividual differences seemingly in excess of those optimal for a fixed-dosage mycophenolate regimen. Combined with experiences of MPA monitoring in other transplant indications, the data have been rationalized to define circumstances in which measurement of MPA concentrations can contribute to improved management of mycophenolate therapy in nonrenal transplant recipients.

Timing of conversion to mammalian target of rapamycin inhibitors is crucial in liver transplant recipients with impaired renal function at transplantation

BACKGROUND

Renal dysfunction, primarily related to long-term use of calcineurin inhibitor-based immunosuppression, is the most common complication after liver transplantation.

OBJECTIVE

To evaluate whether liver transplant recipients with impaired kidney function at transplantation can benefit from early conversion to mammalian target of rapamycin inhibitor therapy (mTORi) compared with patients with late induction of mTORi-based therapy.

MATERIALS AND METHODS

Between 2003 and 2008, therapy was changed to an mTORi-based regimen in 57 patients. Patients were divided into 4 groups: group 1, early conversion (≤3 months after orthotopic liver transplantation) to mTORi therapy, and with impaired perioperative renal function; group 2, early conversion to mTORi therapy, and with normal perioperative renal function; group 3, late conversion to mTORi therapy, and with impaired perioperative renal function; and group 4, late conversion to mTORi therapy, and with normal perioperative renal function.

RESULTS

One month after conversion, the mean (SD) increase in calculated glomerular filtration rate in groups 1 (early conversion) and 3 (late conversion) was comparable: 8 (9) mL/min vs 7 (10) mL/min. At month 3, the increase in calculated glomerular filtration rate between groups 1 and 3 was significant (15 [11] mL/min vs 9 [15] mL/min; P = .04), an effect that persisted at month 6 (16 [12] mL/min vs 10 [12] mL/min; P = .05) and month 12 (22 [14] mL/min vs 12 [15] mL/min; P = .04).

CONCLUSION

In liver transplant recipients with perioperatively impaired renal function, early conversion to mTORi therapy should be performed because this approach seems to be more effective in improving long-term renal function.

Tolerability of everolimus-based immunosuppression in maintenance liver transplant recipients

BACKGROUND

The aim of this study was to evaluate the tolerability of the conversion from calcineurin inhibitor (CNI) to everolimus (ERL) in maintenance liver transplant (LT) recipients.

METHODS

From January 2005 to March 2008, ERL was introduced after LT as maintenance immunosuppressive therapy because of (i) de novo or recurrent cancer after LT, (ii) pre-existing liver carcinoma on the liver explant or (iii) CNI toxicity. CNI dosage was progressively reduced until discontinuation.

RESULTS

The study population included 94 patients, of mean age 57 ± 10. The mean delay between LT and ERL introduction was 5 ± 5 yr. After a mean follow-up of 12 ± 7 months, 70% of the patients did present at least one side effect. The mean trough level of ERL was 6 μg/L at the end of follow-up. Main side effects included hyperlipidemia (37%), dermatitis (19%), mucositis (15%), and proteinuria (18%). Biopsy-proven acute rejection occurred in 9% of patients. Global ERL discontinuation rate was 21% (16% because of side effects).

CONCLUSIONS

The results of our experience indicate that conversion to ERL is associated with adverse effects in 70% of patients leading to drug discontinuation in 16% (and amenable to dose reduction in the remainders). Longer follow-up periods are necessary to capture the impact of ERL fully on renal function and survival in cancer patients.

Metabolic syndrome and liver transplantation: a review and guide to management

Metabolic syndrome is common among liver transplant recipients before and after transplantation. The components of metabolic syndrome are often exacerbated in the post-transplant period by transplant specific factors, such as immunosuppression, and are strong predictors of patient morbidity and mortality. Many aspects of the metabolic syndrome are modifiable. Early recognition, prevention and treatment of post-transplant hypertension, obesity, dyslipidemia and diabetes may impact long-term post-transplant survival. Further study into the prevention and management of these issues in the transplant patient are needed.

Improvement of renal function after the switch from a calcineurin inhibitor to everolimus in liver transplant recipients with chronic renal dysfunction

Chronic renal dysfunction is a frequent and severe complication in solid-organ transplant recipients. Calcineurin inhibitors (CNIs) are the main pathogenic factors of renal dysfunction. Switching from CNIs to nonnephrotoxic drugs, such as mammalian target of rapamycin inhibitors (everolimus and sirolimus), can improve renal function in these patients, but available data about the efficacy and safety of everolimus in liver transplant recipients are scarce. Twenty-one liver transplant recipients (19 males, mean age = 60.6 +/- 7.8 years) with chronic renal dysfunction (creatinine >or= 1.5 mg/dL) were prospectively included. The basal creatinine values were 1.79 +/- 0.39 mg/dL (range = 1.50-2.90 mg/dL). The basal creatinine clearance, evaluated with the Cockroft-Gault formula, was 54.64 +/- 12.47 mL/minute. Everolimus was initiated at a dosage of 0.75 mg twice daily, with target levels of 3 to 8 ng/mL. The withdrawal of CNIs was initiated after the target levels of everolimus were reached. Periodic controls of the weight, arterial pressure, liver function tests, serum creatinine, everolimus levels, proteinuria, creatinine clearance, and glomerular filtration rate at days 30, 90, 180, and 360 were made. After a median follow-up of 19.8 months, the respective creatinine values at 30, 90, 180, and 360 days were 1.68 +/- 0.40 (P = 0.012 with respect to basal values), 1.67 +/- 0.34 (P = 0.107), 1.70 +/- 0.41 (P = 0.521), and 1.57 +/- 0.30 mg/dL (P = 0.047). The respective creatinine clearance values at 30, 90, 180, and 360 days were 58.64 +/- 16.50 (P = 0.013 with respect to basal values), 59.49 +/- 13.27 (P = 0.028), 59.82 +/- 16.83 (P = 0.124), and 64.46 +/- 16.79 mL/minute (P = 0.025). CNIs were withdrawn in 20 recipients (95.2%). Rejection was not detected in any case. In conclusion, the application in liver transplant recipients with chronic renal dysfunction of an immunosuppressive protocol with everolimus and the withdrawal of CNIs was associated with an initial improvement of renal function tests without an increase in the risk of rejection.

Obesity, hyperlipidemia, and metabolic syndrome

1. Obesity is increasingly common among liver transplantation (LT) recipients and donors. Outcomes following LT for selected patients with class I-III obesity are similar to those for nonobese recipients. In patients who are otherwise satisfactory candidates for LT, a high body mass index, as long as it does not present a technical barrier, should not be considered to be an absolute contraindication to LT. 2. The most common causes of death beyond the first year of LT are, in descending order of frequency, graft failure (especially secondary to hepatitis C virus recurrence), malignancy, cardiovascular disease, infections, and renal failure. Metabolic syndrome is an important risk factor for each of these etiologies of posttransplant death. Posttransplant diabetes, posttransplant hypertension, and an original diagnosis of cryptogenic cirrhosis, which is commonly associated with metabolic syndrome, are all associated with an increased risk of post-LT mortality. Features of metabolic syndrome should be screened for and treated in LT recipients. 3. Because of the physiological mechanism of post-LT hypertension, which includes renal arteriolar constriction secondary to calcineurin inhibition, calcium channel blocking agents are a good pharmacological treatment modality and have been shown to be effective in renal protection in randomized controlled trials of posttransplant hypertension. 4. It is rare for dietary changes and weight reduction to result in normalization of the lipid profile. Statins should thus be initiated early in the course of management of post-LT dyslipidemia. Forty milligrams of simvastatin per day, 40 mg of atorvastatin per day, and 20 mg of pravastatin per day are reasonable starting doses for post-LT hypercholesterolemia. It is important to remember that the effects of statin therapy are additive to those of a controlled diet (eg, a Mediterranean diet rich in omega-3 fatty acids, fruits, vegetables, and dietary fiber). 5. Nonalcoholic steatohepatitis, an increasingly common etiology of cirrhosis and liver failure, recurs commonly after LT and may also arise de novo. Treatment should be directed at managing obesity and complications of metabolic syndrome. Optimal immunosuppression in patients with nonalcoholic steatohepatitis is still evolving but should include steroid minimization.

Conversion from a calcineurin inhibitor to everolimus therapy in maintenance liver transplant recipients: a prospective, randomized, multicenter trial

Calcineurin inhibitors (CNIs) contribute to renal dysfunction following liver transplantation. This prospective, randomized, multicenter, 6-month study (with an additional 6 months of follow-up) evaluated whether everolimus with CNI reduction or discontinuation would improve renal function in maintenance liver transplant recipients experiencing CNI-related renal impairment. Patients started everolimus therapy with CNI reduction or discontinuation (n = 72) or continued receiving standard-exposure CNI (n = 73). At month 6, 80% of the patients who had converted to everolimus had discontinued the CNI. The mean change in creatinine clearance (CrCl) from baseline to month 6 was similar between groups (everolimus, 1.0 +/- 10.2 mL/minute; controls, 2.3 +/- 7.8 mL/minute; P = 0.46), so the primary study endpoint (8 mL/minute difference in the change in CrCl) was not achieved. Among patients who continued everolimus according to the protocol, the mean increase in CrCl was 2.1 (n = 53) and 3.8 mL/minute (n = 38) at months 6 and 12, respectively, versus 2.4 (n = 68) and 3.5 mL/minute in controls (n = 51). The high frequency of CNI dose reductions in controls (77% of the patients) and the relatively long mean time post-transplant (>3 years) likely contributed to the small difference in CrCl. Biopsy-proven acute rejection occurred in 1.4% of the patients in each group, with no graft losses. Study drug discontinuation was higher in everolimus-treated patients, and adverse events were more frequent. These data demonstrate that everolimus allows for discontinuation or a major reduction of CNI exposure in liver allograft recipients suffering CNI-related renal dysfunction without a loss of efficacy. Trials targeting earlier conversion post-transplantation are required to confirm the efficacy and safety of everolimus for improving renal function after liver transplantation.

Management of renal dysfunction in the liver transplant recipient

PURPOSE OF REVIEW

Acute and chronic kidney injury following orthotopic liver transplantation (OLT) is associated with increased morbidity and mortality. With the increasing longevity of liver transplant recipients, chronic kidney disease (CKD) has become an increasingly prevalent complication among long-term survivors. This article provides an overview of the literature on suggested risk factors for acute and CKD following OLT and a discussion of an approach to their medical management.

RECENT FINDINGS

In OLT candidates with pretransplant renal dysfunction, the use of interleukin-2 receptor blockers or antithymocyte globulin induction therapy in conjunction with delayed introduction of calcineurin inhibitors may preserve early renal function. In long-term stable OLT recipients with established calcineurin inhibitor nephrotoxicity, calcineurin inhibitor minimization or withdrawal protocols may halt or ameliorate renal dysfunction without compromising patient and graft survival. However, large-scale, multicenter, randomized controlled trials are still needed.

SUMMARY

The occurrence of acute kidney injury is common immediately after OLT, whereas the incidence of CKD and end-stage renal disease increases with time. Identifying patients at risk for acute kidney injury and CKD following OLT and early implementation of measures to preserve, halt, or ameliorate the progression of renal dysfunction should be an integral part in the management of OLT recipients.

Sirolimus in liver transplant recipients with renal dysfunction offers no advantage over low-dose calcineurin inhibitor regimens

The purpose of this study is to review the clinical experience with sirolimus immunosuppression in liver transplant patients with calcineurin inhibitor-induced chronic renal insufficiency. The study design is a case-control retrospective series. Fifty-seven liver transplant patients with renal insufficiency that were started on sirolimus at greater than 90 days postoperatively and treated for more than 90 days were identified. A control group of 57 patients maintained on low-dose calcineurin inhibitors, matched for gender, year of transplant, and baseline creatinine clearance, was also identified. There were no significant differences in the absolute creatinine clearance values between the sirolimus and control groups from 6 months before sirolimus conversion to 12 months after sirolimus conversion. Patients exposed to calcineurin inhibitors for more than 5 years or those with an initial creatinine clearance of less than 30 mL/minute who were converted to sirolimus did worse than control patients maintained on low-dose calcineurin inhibitors. Progression to renal replacement therapy, episodes of acute and chronic rejection, and death were similar between the sirolimus and control groups. The overall prevalence of side effects was significantly higher in the sirolimus group compared with the control group, although these were generally tolerable in most patients. In conclusion, this study suggests that conversion to sirolimus in liver transplant patients with chronic renal insufficiency is associated with stabilization of renal function but confers no additional benefit to low-dose calcineurin inhibitor regimens and may in fact be disadvantageous in patients with a creatinine clearance of less than 30 mL/minute.

Early renal function post-liver transplantation is predictive of progressive chronic kidney disease

OBJECTIVE

With improvements in long-term results after liver transplantation, chronic kidney disease (CKD) has become a highly relevant problem. The early measurement of the glomerular filtration rate (GFR) can identify those patients who are at risk of developing CKD years after liver transplantation. The aims of this study were to describe the prevalence of CKD 5 years after liver transplantation, to study the correlation between measured GFR early after transplantation and late renal function and to identify patients at risk of developing late CKD after liver transplantation.

MATERIAL AND METHODS

A total of 152 patients who were at least 5 years post-liver transplantation were studied. Measured GFR with Chromium EDTA or iohexol clearance was followed-up for 5 years (n 52) and 10 years (n 41).

RESULTS

The overall decrease in measured GFR was 36% after 5 years and 42% after 10 years. Eight patients (5%) required renal replacement therapy. GFR levels pretransplantation showed a poor correlation with later renal function (at 5 years). The GFR measured at 3 months and 1 year post-transplantation correlated well with measured GFR at 5 years post-transplantation. Multivariate analysis showed that measured GFR of less than 30 ml at 3 months post-transplantation was significantly associated with CKD at 5 years post-transplantation.

CONCLUSIONS

GFR levels below 30 ml/min/1.73 m2 at 3 months post-liver transplantation are associated with the development of later CKD Stage 4-5 long after liver transplantation. The importance of this finding is the possibility of identifying at an early stage those individuals that may benefit from early implementation of calcineurin sparing or a withdrawal regimen with the goal of preserving long-term renal function.

Calcineurin inhibitor-sparing regimens in solid organ transplantation: focus on improving renal function and nephrotoxicity

BACKGROUND

The calcineurin inhibitors (CNIs), cyclosporine and tacrolimus, have had a revolutionary effect on the overall success of renal transplantation through reduction in early immunologic injury and acute rejection rates. However, the CNIs have a significant adverse impact on renal function and cardiovascular disease, and extended long-term graft survival has not been achieved. The recognition of these effects sparked interest in CNI-sparing strategies. Strategies to limit CNI exposure include CNI minimization, avoidance, and withdrawal. We sought to review the impact of CNI-sparing strategies in kidney, liver, and heart transplantation.

MATERIALS AND METHODS

A PubMed search 1966 to August 2006 was conducted to identify relevant research articles, and the references of these articles as well as the authors' personal files were reviewed.

RESULTS

Calcineurin inhibitor minimization using mycophenolate mofetil or sirolimus may be associated with a modest increase in creatinine clearance (CrCl) and a decrease in serum creatinine (SCr) in the short term. Despite improvement in CrCl or SCr, CNI nephrotoxicity and chronic allograft nephrotoxicity are progressive over time when CNI exposure is maintained. In kidney transplantation, the tubulo-interstitial and glomerular damage are irreversible. Mycophenolate mofetil may improve renal outcomes during CNI minimization more than sirolimus, and antibody induction may be effective to limit CNI exposure, but longer-term follow-up data are required. Use of sirolimus with mycophenolate mofetil or azathioprine to avoid CNI exposure de novo has improved glomerular filtration rate for at least two yr in most studies in kidney transplantation; however, experience is limited in liver and heart transplantation, and reports of delayed graft function and wound healing with sirolimus may have dampened enthusiasm for de novo use. Late CNI withdrawal has achieved variable results, possibly because withdrawal was attempted after the kidney damage was too extensive. Early CNI withdrawal, prior to significant graft damage, has generally improved CrCl and markers of fibrosis and decreased chronic allograft lesions, a finding also observed with sirolimus in most CNI avoidance studies. Successful withdrawal appears to be more effective than CNI minimization.

CONCLUSIONS

Calcineurin inhibitors are associated with significant nephrotoxicity and chronic kidney damage. Minimization is associated with a modest increase in renal function, but persistent damage is observed on biopsies as long as the CNIs are continued. Avoidance is hampered by lack of experience and possible sirolimus-induced side effects. CNI withdrawal may be the best option by delivering CNIs during the early period of immunologic graft injury and then converting them to less nephrotoxic agents before significant renal damage occurs.

Sirolimus: efficacy in liver transplant patients with nephrotoxicity and renal insufficiency

Nephrotoxicity is a complication of patients undergoing orthotopic liver transplantation. Herein we present several factors that play an important role in this complication.

Sirolimus conversion in liver transplant recipients with renal dysfunction: a prospective, randomized, single-center trial

This pilot trial was designed to assess the safety and efficacy of SRL in liver transplant recipients with renal dysfunction. Forty patients with renal dysfunction (24-hr CrCl 40-80 mL/min) were randomized to be withdrawn from the calcineurin inhibitor (CNI) and receive sirolimus (SRL) or to continue CNI (control arm). Improvement in 24-hour CrCl was seen in the SRL arm at 3 months (75 mL/min SRL vs. 56 mL/min control, P=0.012), whereas at 12 months there was a trend toward improvement in the SRL arm (72 mL/min SRL vs. 58 mL/min control, P=0.09). Two patients, one in each arm, developed steroid-sensitive rejection. Side effects of SRL were limited and included hyperlipidemia requiring treatment (15%), pruritus (5%), and mouth sores (25%). In this trial, SRL-based immunosuppression was a safe alternative to CNI. Although early improvements were observed, withdrawing CNI and replacing it with SRL did not result in a statistically significant improvement in renal function at 12 months of follow-up.

Effects of sirolimus vs. calcineurin inhibitors on renal dysfunction after orthotopic liver transplantation

Small uncontrolled series have suggested that sirolimus favorably impacts renal function after orthotopic liver transplantation (OLT). We sought to retrospectively compare renal dysfunction between cohorts exposed to sirolimus-based and calcineurin inhibitor-based immunosuppression. We retrospectively studied 79 patients converted to sirolimus-based immunosuppression and 100 control subjects continued on calcineurin inhibitor-based immunosuppression after OLT at our institution from 2000 to 2005. We collected clinical, demographic, and medication history. Renal dysfunction was defined as two or more wk of creatinine > or =2.0 mg/dL. Cohorts were compared using Kaplan-Meier survival analysis and Cox proportional hazards modeling. Patients began sirolimus a median 83 d post-OLT and were followed on the medication for median 359 d. Patients in both the sirolimus and calcineurin inhibitor cohorts had median creatinine 1.2 mg/dL at study entry. Sirolimus-based immunosuppression was associated with a 1.8 (0.8-4.3, p = 0.17) hazards ratio for renal dysfunction. Adjusting for presence of hepatocellular carcinoma, combined kidney/liver transplantation, and age, the hazards ratio was 2.0 (0.8-4.8, p = 0.13). These point estimates were not substantially altered after subgroup analysis of sirolimus as the lone immunosuppressant, duration of exposure, and time between OLT and sirolimus conversion. In conclusion, our retrospective, controlled study showed that conversion to sirolimus after OLT did not protect against renal dysfunction. The effect of sirolimus on renal function will need to be prospectively evaluated in a prospective, randomized trial.

Sirolimus and liver transplantation: clinical implications for hepatocellular carcinoma

Sirolimus (SRL) is a macrolide antibiotic that has potent antifungal and immunosuppressive properties; preclinical studies suggest that SRL may possess a significant antiproliferative influence in vitro. Recently, several studies have documented a negative effect by SRL on both primary tumor growth and the proliferation of metastatic foci in various rodent models of hepatocellular carcinoma (HCC). Orthotopic liver transplantation (OLT) is increasingly becoming a viable treatment option for patients with end stage liver disease and concomitant HCC. As such, an immunosuppressive agent with antineoplastic activity is inherently attractive in the setting of OLT for malignancy. Regrettably, the cumulative experience with SRL-based immunosuppression in this patient population is limited. Herein, the authors review the experience to date with SRL as a primary immunosuppressive agent following OLT, and discuss the clinical implications of SRL-based therapy in OLT recipients with cirrhosis and cancer.

Long-term care of the liver transplant recipient

As survival increases after liver transplantation, common issues that arise involve immunosuppression-related complications and primary health care. Proper emphasis on the prevention and treatment of post-liver transplant complications, such as diabetes mellitus, dyslipidemia, renal dysfunction, osteoporosis, and obesity, requires careful screening and long-term surveillance to minimize the progression of these complications. Active involvement by internists and subspecialists is necessary and a multidisciplinary approach should be undertaken. Liver transplantation should be viewed as a lifelong commitment by both patient and physician.

Avoiding calcineurin inhibitors in the early post-operative course in high-risk liver transplant recipients: The role of extracorporeal photopheresis

The aim of this work is to report on the results of a single-center, prospective study on the feasibility of calcineurin-inhibitor (CNI)-staggered immunosuppression by use of extracorporeal photopheresis (ECP) in liver transplant (LT) recipients at risk of renal and neurological complications. Patients were matched on a 1:1 basis with historical controls on standard CNI immunosuppression. ECP patients were treated with ECP plus antimetabolites and/or steroids, while CNIs were withheld until clinically indicated. Thirty-six patients were evaluated: 18 ECP patients and 18 controls. ECP was tolerated in 100% of cases. CNI were introduced at a median of 8 days (4-55) in 17 ECP patients, while one patient was on a fully CNI-sparing regimen 22 months after LT. Acute rejection occurred in 27.7% patients in ECP (5/18) versus 16.7% in controls (3/18) (P = ns) with a shorter time to rejection in ECP (36 +/- 31.3 days vs. 83.6 +/- 65.6 days; P = ns). All rejection episodes were amenable to medical treatment. Neurological and renal complications occurred in 22.2% (4/18) of patients in either group, but led to in-hospital mortality in 3 patients among controls versus 1 in ECP (P = ns). One-, 6-, and 12-month survival rates were 94.4, 88.1, and 88.1% in ECP versus 94.4, 77.7, and 72.2% among controls (P < 0.0001). ECP seems to allow for management of high-risk LT recipients in the early post-transplant course and reduction of CNI-related mortality. Continued data validation is favored to assess the impact of ECP on long-term graft and patient survival.

Switch to 1.5 grams MMF monotherapy for CNI-related toxicity in liver transplantation is safe and improves renal function, dyslipidemia, and hypertension

Although mycophenolate mofetil (MMF) monotherapy has been successfully used in liver transplant recipients suffering from calcineurin-inhibitor (CNI)-related chronic toxicity, still no consensus has been reached on its safety, efficacy and tolerability. We attempted the complete weaning off CNI in 42 individuals presenting chronic renal dysfunction and/or dyslipidemia and/or arterial hypertension and simultaneously introduced 1.5 gm/day MMF. CNI could be completely withdrawn in 41 cases. A total of 32 (75%) patients are currently on <or=1.5 gm/day of MMF. Mean follow-up from the introduction of MMF is 31.5 months and mean length of follow-up from the beginning of MMF monotherapy is 27.3 months. Renal function improved in 31/36 (89%) cases. Blood levels of cholesterol and triglycerides decreased in 13 of 17 (76%) and 15 of 17 (89%) patients, respectively. Arterial hypertension improved in 4 of 5 (80%) cases. A total of 8 patients showed a single episode of fluctuation of liver function tests during tapering off CNI. This feature was interpreted as an acute rejection (AR), based on the resolution of the clinical setting after escalation of MMF daily dose to 2 gm. A further patient developed a biopsy-proven AR insensitive to MMF adjustment, requiring reinstitution of the CNI dose. No deaths or major toxicity requiring MMF discontinuation occurred. In conclusion, low dose MMF monotherapy is safe, effective, and well tolerated.

Drug insight: novel small molecules and drugs for immunosuppression

Gastrointestinal diseases can result from the inadequate or excessive response of the immune system to self or innocuous antigens. Moreover, the physiologic activation of the immune system against non-self antigens is a major clinical problem in liver organ transplantation. At present, many drugs are available that suppress the activation of the immune system, although most of the currently used immunosuppressive drugs lack specificity in terms of their molecular targets and, therefore, have the potential to generate numerous side effects. The advances that have been made in understanding the molecular events that underlie the activation of the immune system have led to the development of a new generation of 'small molecules' that are endowed with immunosuppressive properties and can serve as immunomodulatory agents. Among these new small molecules, inhibitors of Janus kinase 3, p21-Rac1 and p38 mitogen-activated protein kinase represent the most innovative approach to immunosuppression, and could be a promising alternative to current immunosuppressive therapies. Here, we report on the progress that has been made in the development of small molecules in the field of gastroenterology.

Liver and kidney transplantation for polycystic liver and kidney-renal function and outcome

BACKGROUND

Polycystic liver disease (PLD) is a rare disorder frequently associated with polycystic kidney disease (PKD). Transplantation is a treatment option for these patients. Because of preservation of hepatic function in these patients, liver transplantation is not routinely utilized. We report a large series of PLD patients and their outcomes following liver and kidney transplantation.

METHODS

Fourteen patients underwent orthotopic liver transplantation (OLTx) for PLD between 1987 and 2003. Twelve patients had PKD combined with PLD. Nine patients received only liver transplantation. Five patients had combined liver and kidney transplantation. Thirteen patients (93%) survived for at least one year following liver transplantation. Two out of eight patients who received solitary liver transplantation later required kidney transplantation.

RESULTS

Pretransplant glomerular filtration rate (GFR) in patients with PKD was 75.8+/-25.4 ml/min/1.73 m. One year later, GFR was 37.2+/-8.3 ml/min/1.73 m. Kaplan-Meier analysis showed that one- and two-year graft survival for combined liver and kidney transplantation was 80% (n=5), whereas graft survival for solitary liver transplantation was 100% (n=9). Mean survival of patients who had combined liver and kidney transplantation was 46.7+/-54.2 months (n=5), whereas the mean survival for solitary liver transplant patients was 80.4+/-68.6 months (n=9) (P=0.36).

CONCLUSION

Transplantation is an excellent option for PLD with dramatic improvement in quality of life and acceptable morbidity. For combined liver and kidney transplantation one- and two-year patient survival rates were similar to combined transplantation for other indications. For patients with acceptable renal function at time of transplantation, solitary liver transplantation has an excellent outcome.